Solar energy is radiant light and heat from the Sun that is harnessed using a range of technologies such as solar power to generate electricity, solar thermal energy, and solar architecture. It is an essential source of renewable energy, and its technologies are broadly characterized as either passive solar or active solar depending on how they capture and distribute solar energy or convert it into solar power. Active solar techniques include the use of photovoltaic systems, concentrated solar power, and solar water heating to harness the energy. Passive solar techniques include orienting a building to the Sun, selecting materials with favorable thermal mass or light-dispersing properties, and designing spaces that naturally circulate air.
Solar thermal energy (STE) is a form of energy and a technology for harnessing solar energy to generate thermal energy for use in industry, and in the residential and commercial sectors.
A parabolic trough is a type of solar thermal collector that is straight in one dimension and curved as a parabola in the other two, lined with a polished metal mirror. The sunlight which enters the mirror parallel to its plane of symmetry is focused along the focal line, where objects are positioned that are intended to be heated. In a solar cooker, for example, food is placed at the focal line of a trough, which is cooked when the trough is aimed so the Sun is in its plane of symmetry.
High-temperature electrolysis is a technology for producing hydrogen from water at high temperatures or other products, such as iron or carbon nanomaterials as higher energy lowers needed electricity to split molecule and opens up new, potentially better electrolytes like molten salts or hydroxides.
Nevada Solar One is a concentrated solar power plant, with a nominal capacity of 64 MW and maximum steam turbine power output up to 72 MW net (75 MW gross), spread over an area of 400 acres (160 ha). The projected CO2 emissions avoided is equivalent to taking approximately 20,000 cars off the road. The project required an investment of $266 million USD, and the project officially went into operation in June 2007. Electricity production is estimated to be 134 GWh (gigawatt hours) per year.
Gemasolar is a concentrated solar power plant with a molten salt heat storage system. It is located within the city limits of Fuentes de Andalucía in the province of Seville, Spain.
Solar power is a fast-growing industry in Australia. As of September 2023, Australia's over 3.60 million solar PV installations had a combined capacity of 32.9 GW photovoltaic (PV) solar power, of which at least 3,823 MW were installed in the preceding 12 months. In 2019, 59 solar PV projects with a combined capacity of 2,881 MW were either under construction, constructed or due to start construction having reached financial closure. Solar accounted for 12.4% of Australia's total electrical energy production in 2021.
Solar Systems is an Australian company that has constructed three concentrated solar power stations in remote Indigenous communities the Northern Territory, Australia, using 30 solar concentrator dishes which together generated 720 kilowatts (970 hp) and 1,555,000 kilowatt-hours (5,600,000 MJ) per year. The sites are in Hermannsburg, Yuendumu and Lajamanu. This represents a saving of 420,000 litres of diesel fuel and 1550 tonnes of greenhouse gas emissions.
Renewable energy in Australia is mainly based on biomass, solar, wind, and hydro generation. Over a third of electricity is generated from renewables, and is increasing, with a target to phase out coal power before 2040. Wind energy and rooftop solar have particularly grown since 2010. The growth has been stimulated by government energy policy in order to limit the rate of climate change in Australia that has been brought about by the use of fossil fuels. Pros and cons of various types of renewable energy are being investigated, and more recently there have been trials of green hydrogen and wave power.
A solar thermal power station was to be built in Cloncurry, in north-west Queensland. The solar thermal power station was planned to have a nameplate capacity of 10 MW and deliver about 30 gigawatt-hours of electricity a year, enough to power the whole town.
Sopogy was a solar thermal technology supplier founded in 2002 at the Honolulu, Hawaii-based clean technology incubator known as Energy Laboratories. The company began its research on concentrating solar thermal energy to produce solar steam and thermal heat for absorption chillers or industrial process heat. The company has also developed applications that incorporate its solar collectors to generate electricity and desalination. Sopogy's name origin comes from industry key words "So" from solar "po" from power and "gy" from energy and technology. The company has its OEM and IPP sales teams along with research and development located in Honolulu, and in 2006 expanded its manufacturing, C&I and oil and gas sales teams in its Silicon Valley facility. Pacific Business News and Greentech Media reported that the VC-funded micro-concentrator solar power firm was shutting down operations based on statements from its President David Fernandez, however Hitachi Power Systems acquired Sopogy in a private transaction in 2014.
The Solana Generating Station is a solar power plant near Gila Bend, Arizona, about 70 miles (110 km) southwest of Phoenix. It was completed in 2013. When commissioned, it was the largest parabolic trough plant in the world, and the first U.S. solar plant with molten salt thermal energy storage. Built by the Spanish company Abengoa Solar, the project can produce up to 280 megawatts (MW) gross, supplied by two 140 MW gross (125 MW net) steam turbine generators: enough electricity to meet the needs of approximately 70,000 homes and obviate the emission of roughly 475,000 tons of CO2 every year. Its name is the Spanish term for "sunny spot".
Concentrated solar power systems generate solar power by using mirrors or lenses to concentrate a large area of sunlight into a receiver. Electricity is generated when the concentrated light is converted to heat, which drives a heat engine connected to an electrical power generator or powers a thermochemical reaction.
SolarReserve was a developer of utility-scale solar power projects which include Concentrated Solar Power (CSP) and Photovoltaic (PV) technology. The company has commercialized solar thermal energy storage technology that enables solar power tower CSP plants to deliver electricity day and night. In this technology, a molten salt is used to capture the energy from the sun and store it. When electricity is needed, the stored liquid salt is used to turn water into steam to turn a turbine and generate electricity.
eSolar is a privately held company that develops concentrating solar power (CSP) plant technology. The company was founded by the Pasadena-based business incubator Idealab in 2007 as a developer of CSP plant technology. The company aims to develop a low cost alternative to fossil fuels through a combination of small heliostats, modular architecture, and a high-precision sun-tracking system. In October 2017, an article in GreenTech Media suggested that eSolar ceased business in late 2016.
Australia is well placed to harness solar thermal energy. Solar thermal energy is used in three main ways: solar hot water heating, production of steam for electricity generation and space heating through building design.
The Ashalim power station is a concentrated solar power station in the Negev desert near the kibbutz of Ashalim, south of the district city of Be'er Sheva in Israel. It consists of three plots with three different technologies the station combines 3 kinds of energy: solar thermal energy, photovoltaic energy, and natural gas.
The Big Dish is a parabolic dish concentrator developed by the Australian National University's Solar Thermal Group. The initial prototype, SG3 , was constructed on the Canberra campus of the Australian National University in 1994. A modified version of SG3 was exported to Ben-Gurion National Solar Energy Center at the Ben Gurion University in Israel. In 2006, a joint project led by the Solar Thermal Group with commercial partner Wizard Power, and funding from Australian's Government's Renewable Energy Development Initiative, began the design and construction of SG4 . SG4 is located next to the SG3 dish, and was completed in 2009.
The Australian Renewable Energy Agency (ARENA) is an independent agency of the Australian federal government, established in 2012 to manage Australia's renewable energy programs, with the objective of increasing supply and competitiveness of Australian renewable energy sources.
